# Patent

## Title
Dynamic channel bonding partial service triggering

## Abstract

A method and computing device for transitioning into and out of partial service mode to make bandwidth available for other resources. A trigger value is set for a channel, where a first and second cable modem have registered to use the channel, and where the first cable modem is a bonded channel modem that utilizes a bonding group that includes the channel and at least one other channel. A modulation mode for the channel is monitored. The channel is transitioned from full service mode to partial service mode when the channel is in full service mode and monitoring detects that the modulation mode is less than or equal to the trigger value. The channel is transitioned from partial service mode to full service mode when the channel is in partial service mode and the modulation mode for the channel is greater than the trigger value.

## Background
BACKGROUND
Data over cable service interface specification (DOCSIS) is an international telecommunications standard that permits the addition of high-speed data transfer to an existing cable television system. To maintain cross-version compatibility across all versions of DOCSIS, cable television operators utilize cable modems that support DOCSIS 1.X, 2.X, and 3.0, and that fall back to the highest supported version in common between both endpoints. Cable television operators use DOCSIS 3.0 to provide two-way communication over their existing hybrid fiber-coaxial (HFC) infrastructure.
An HFC network is a broadband network that combines optical fiber and coaxial cable. The HFC network is a two-way communication network between a cable modem termination system (CMTS) and a cable modem. The CMTS is communication equipment typically located in a cable operator's headend facility. The CMTS collects and processes communication signals, distributes those signals to customer locations using downstream channels, and receives other communication signals from the customer locations on upstream channels. The cable modem is a communication device that receives the communication signals on the downstream channels from the CMTS, and transmits the other communication signals to the CMTS on the upstream channels. The cable modem may be a standalone device that connects to the Internet, or integrated with a set-top box.
The DOCSIS 1X and 2.X specifications describe the channel frequency and modulation characteristics for downstream and upstream transmissions. When the CMTS communicates with a device, the DOCSIS 1.X or 2.X cable modem at a customer location uses the frequencies (channels) of the CMTS transmitter and receiver to which the modem is physically connected to carry the downstream and upstream transmissions. The term “channel” as used herein is synonymous with the term “receiver”. If the channel becomes impaired, the modulation mode of the channel can drop, resulting in a reduction in the bandwidth to the device.
Channel bonding is a DOCSIS 3.0 feature that enables a DOCSIS 3.0 cable modem at a customer location to use multiple downstream channels, or multiple upstream channels, together at the same time. For example, a cable modem configured with four upstream channels can use DOCSIS 3.0 channel bonding to increase the throughput of the upstream communication with the CMTS. The cable modem distributes, or segments, the data packets among the four channels in an upstream bonding group and transmits the data packets to the CMTS in parallel, rather than in series. When the upstream bonding group operates in full service mode, the CMTS receives and reassembles the data packets on all four channels in the upstream bonding group. If there is a problem receiving data packets on a CMTS receiver, due to an upstream channel that is associated with the receiver being impaired or unavailable, the CMTS cannot properly reassemble the data packets for the upstream bonding group and data loss or throughput degradation will result. The detection of this problem will allow communication to continue between the CMTS and cable modem by transitioning the upstream bonding group to operate in partial service mode by disabling data grant scheduling on the faulty receiver/channel.
When DOCSIS 1.X, 2.X, and 3.0 modems are registered to use a channel that becomes impaired, a decrease in bandwidth on the impaired channel, which can also result from a lowering of the modulation profile due to noise, is a greater impact on the DOCSIS 1.X and 2.X modems, because the DOCSIS 3.0 modem has other bonded channels to use for data passing as long as the impaired channel is in partial service mode. If the DOCSIS 3.0 modem is not yet in partial service mode, the DOCSIS 3.0 modem cannot reassemble the packets. In addition, the reduction in bandwidth may cause an increase in utilization based on the bandwidth size, and may trigger unnecessary load balancing with the possibility of losing modems when they attempt to move to another channel. Furthermore, a configuration change by the cable operator may cause a decrease in the modulation mode. There is a need for a method of controlling when a channel transitions to partial service mode to make valuable bandwidth available for other resources. The presently disclosed invention satisfies this demand.
SUMMARY
Aspects of the present invention provide a method and computing device for transitioning into and out of partial service mode to make valuable bandwidth available for other resources. The method sets a trigger value for a channel, where a first cable modem and a second cable modem have registered to use the channel, and where the first cable modem is a bonded channel modem that utilizes a bonding group that includes the channel and at least one other channel. The method then monitors a modulation mode for the channel. The method transitions the channel from full service mode to partial service mode when the channel is in full service mode and the monitoring detects that the modulation mode is less than or equal to the trigger value. The method transitions the channel from partial service mode to full service mode when the channel is in partial service mode and the modulation mode for the channel is greater than the trigger value.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram that illustrates one embodiment of the hardware components of a system that performs the present invention.
FIG. 2 is a flow diagram that illustrates a method of transitioning into and out of partial service mode to make valuable bandwidth available for other resources according to one embodiment of the present invention.



DETAILED DESCRIPTION
FIG. 1 is a block diagram that illustrates one embodiment of the hardware components of a system that performs the present invention. A broadband network 100 includes an Internet protocol (IP) network 110, cable modem termination system (CMTS) 120, cable network 130, customer location A 140, customer location B 180, and customer location C 190. The broadband network 100 shown in FIG. 1 may include any number of interconnected IP network 110, CMTS 120, cable network 130, customer location A 140, customer location B 180, and customer location C 190 components.
The IP network 110 shown in FIG. 1, in one embodiment, is a public communication network or wide area network (WAN) that connects to the CMTS 120. The present invention also contemplates the use of comparable network architectures including a LAN, a personal area network (PAN) such as a Bluetooth network, a wireless LAN (e.g., a wireless-fidelity (Wi-Fi) network), peer-to-peer overlay network, and a virtual private network (VPN). The system contemplates comparable network architectures and protocols such as Ethernet and transmission control protocol.
The cable network 130 shown in FIG. 1, in one embodiment, is a hybrid fiber-coaxial (HFC) network. The cable network 130 is a data and video content network that provides two-way communication between the CMTS 120 and customer location A 140, customer location B 180 or customer location C 190. The downstream communication path is from the CMTS 120 to a customer location (e.g., customer location A 140, customer location B 180, or customer location C 190). The upstream communication path is from a customer location (e.g., customer location A 140, customer location B 180, or customer location C 190) to the CMTS 120.
The CMTS 120, in one embodiment, is communication equipment located in a cable operator's headend or hubsite that provides high-speed data services, such as cable Internet or voice over Internet protocol, to cable subscribers. The CMTS 120 shown in FIG. 1 includes at least one computing device, each having one or more processors, that provides customer location A 140, customer location B 180, and customer location C 190 with various services and connections. This includes support for data over cable service interface specification (DOCSIS) 122 services (e.g., DOCSIS 1.X, DOCSIS 2.X, and DOCSIS 3.0), partial service triggering program 124, channel trigger values 126, IP network 110 connections, and cable network 130 connections. The partial service triggering program 124 and channel trigger values 126, together with the cable modem 142, performs the method of the present invention disclosed in the exemplary embodiments depicted in FIG. 2. The IP network 110 connections enable the CMTS 120 to provide access to external services such as video servers, public switched telephone network voice, multimedia messages, and Internet data.
Customer location A 140 shown in FIG. 1 is a customer's home, business, or another location where the customer accesses the cable service. In one embodiment, customer location A 140 includes a cable modem 142, set-top box 144, and display device 146. In other embodiments, the set-top box 144 is a digital television (DTV) Converter (DTC) or other customer-premises equipment (CPE), and the display device 146 is an Internet protocol television (IPTV) or analog television. In yet another embodiment, the set-top box 144 includes the cable modem 142.
The cable modem 142 shown in FIG. 1, in one embodiment, is a general-purpose computing device that performs the present invention together with the partial service triggering program 124 and channel trigger values 126 on the CMTS 120. A bus 150 is a communication medium connecting a processor 155, data storage device 160 (such as a serial ATA (SATA) hard disk drive, optical drive, small computer system interface (SCSI) disk, flash memory, or the like), communication interface 165, and memory 170 (such as random access memory (RAM), dynamic RAM (DRAM), non-volatile computer memory, flash memory, or the like). The communication interface 165 connects the cable modem 142 to the cable network 130 and allows for two-way communication of data and content. In one embodiment, the set-top box 144 includes the cable modem 142 implemented as an application-specific integrated circuit (ASIC).
The processor 155 performs the disclosed methods by executing sequences of operational instructions that comprise each computer program resident in, or operative on, the memory 170. The reader should understand that the memory 170 may include operating system, administrative, and database programs that support the programs disclosed in this application. In one embodiment, the configuration of the memory 170 of the cable modem 142 includes a DOCSIS 3.0 program 172. The DOCSIS 3.0 program 172 is an implementation of DOCSIS 3.0 that, together with the partial service triggering program 124 and channel trigger values 126, performs the method of the present invention disclosed in the exemplary embodiments depicted in FIG. 2. When the processor 155 performs the disclosed method, it stores intermediate results in the memory 170 or data storage device 160. In another embodiment, the processor 155 may swap these programs, or portions thereof, in and out of the memory 170 as needed, and thus may include fewer than all of these programs at any one time.
Customer location B 180 shown in FIG. 1 is a customer's home, business, or another location where the customer accesses the cable service. In one embodiment, customer location B 180 includes hardware components (not shown) similar to those shown in customer location A 140. The only difference is that customer location B 180 includes a DOCSIS 1.1 modem 182 that implements the DOCSIS 1.1 specification to replace the cable modem 142 that implements the DOCSIS 3.0 specification in customer location A 140.
Customer location C 190 shown in FIG. 1 is a customer's home, business, or another location where the customer accesses the cable service. In one embodiment, customer location C 190 includes hardware components (not shown) similar to those shown in customer location A 140. The only difference is that customer location C 190 includes a DOCSIS 2.0 modem 192 that implements the DOCSIS 2.0 specification to replace the cable modem 142 that implements the DOCSIS 3.0 specification in customer location A 140.
FIG. 2 is a flow diagram that illustrates a method of transitioning into and out of partial service mode to make valuable bandwidth available for other resources according to one embodiment of the present invention. In one embodiment, the present invention can apply to upstream channels only. In another embodiment, the present invention can apply to downstream channels only. In yet another embodiment, the present invention can apply to either upstream channels or downstream channels, or to both upstream channels and downstream channels.
The process 200 shown in FIG. 2 begins when the CMTS 120 sets a trigger value for a channel (step 205). In one embodiment, a cable operator sends a configuration parameter to the CMTS 120 that causes the CMTS 120 to store a trigger value for a specified upstream or downstream channel. Once the trigger value is set, the process 200 determines when to trigger into partial service mode (step 210), and when to trigger out of partial service mode (step 235).
To determine when to trigger into partial service mode (step 210), the process 200 monitors the modulation mode for the channel (step 215). In one embodiment, the modulation mode for the channel is whether the channel is operating in 64 QAM, 32 QAM, 16 QAM or 8 QAM, and the trigger value is 16 QAM. In other embodiments, the present invention contemplates other modulation modes for the channel (e.g., 256 QAM, 128 QAM, and the like), other modulation modes for a spectrum group, and priorities for a modulation profile hopping rule. While the modulation mode for the channel is greater than the trigger value (step 220, N branch), the process 200 continues to monitor the modulation mode for the channel (step 215). When the modulation mode for the channel is less than or equal to the trigger value (step 220, Y branch), the process 200 transitions the channel to partial service mode (step 225). The process 200 then notifies all bonded channel modems (i.e., DOCSIS 3.0 modems) that the channel is unusable (step 230).
To determine when to trigger out of partial service mode (step 235), the process 200 monitors the modulation mode for the channel (step 240). While the modulation mode for the channel is less than or equal to the trigger value (step 245, N branch), the process 200 continues to monitor the modulation mode for the channel (step 240). When the modulation mode for the channel is greater than the trigger value (step 245, Y branch), the process 200 transitions the channel to full service mode (step 250). The process 200 then notifies all bonded channel modems (i.e., DOCSIS 3.0 modems) that the channel is usable (step 255).
In the method shown in FIG. 2, the purpose of transitioning into partial service mode is to free valuable bandwidth for DOCSIS 1.X and 2.X modems, while temporarily transitioning DOCSIS 3.0 bonded channel modems into partial service. The purpose of transitioning back to full service mode is to allocate available valuable bandwidth for DOCSIS 3.0 bonded channel modems. The trigger value is a configuration parameter for transitioning into and out of partial service mode. In one embodiment, the cable operators are provided the trigger value, thereby giving them full control of this functionality. The configuration parameter allows the cable operator to select a modulation mode used to trigger the transition into and out of partial service mode for a particular channel. In various embodiments, the configuration parameter is a modulation mode per channel association, a modulation mode configurable per spectrum group, and the modification of a priority of an existing modulation profile hopping rule. Furthermore, the configuration parameter has a setting that disables the functionality if the cable operator does not want to use it.
The following two examples illustrate the method of transitioning into and out of partial service mode shown in FIG. 2 in which a DOCSIS 1.1 modem, DOCSIS 2.0 modem, and DOCSIS 3.0 modem have registered to use an upstream channel. The first example illustrates the impact on the bandwidth to the DOCSIS 1.1 modem, DOCSIS 2.0 modem, and DOCSIS 3.0 modem when the innovation of the present invention is disabled. The second example illustrates the improvements realized when the innovation of the present invention is enabled. Finally, even though these examples focus on an upstream channel, one skilled in the art will realize that these examples are easily adaptable to downstream channels.
With the innovation of the present invention disabled, a DOCSIS 1.1 modem 182, DOCSIS 2.0 modem 192, and DOCSIS 3.0 cable modem 142 registers to use an upstream channel on the CMTS 120. The channel is operating in 64 QAM modulation mode with spare hopping modulation modes such as 32 QAM, 16 QAM, and 8 QAM. When the channel becomes impaired and the modulation mode drops to 16 QAM, this greatly reduces the available bandwidth for all modems, especially the DOCSIS 1.1 modem 182 and DOCSIS 2.0 modem 192. Since the DOCSIS 3.0 cable modem 142 is bonded, it still has other channels to use for data passing and only takes a small overall bandwidth hit. If the channel becomes more impaired and the modulation mode drops to 8 QAM, the DOCSIS 1.1 modem 182 and DOCSIS 2.0 modem 192 are really limited in their ability to pass data, but the DOCSIS 3.0 cable modem 142 still has other channels to use. If the channel impairment is bad enough, the DOCSIS 1.1 modem 182 and DOCSIS 2.0 modem 192 may not be able to pass data or even stay registered because there is not enough bandwidth to support all of the ranging requests. The reduction of bandwidth (causing an increase in utilization based on bandwidth size) may also trigger unnecessary load balancing with the possibility of losing modems when they attempt to move to another channel. If the channel impairment then goes away and the modulation mode for the channel increases to 64 QAM, the channel may now be underutilized if the modems were moved by load balancing. In addition, since the DOCSIS 1.1 modem 182 and DOCSIS 2.0 modem 192 also carry voice traffic, the reduction of bandwidth may also result in dropping voice calls or the failure to initiate a voice call.
With the innovation of the present invention enabled, a DOCSIS 1.1 modem 182, DOCSIS 2.0 modem 192, and DOCSIS 3.0 cable modem 142 registers to use an upstream channel on the CMTS 120. The channel is operating in 64 QAM modulation mode with spare hopping modulation modes such as 32 QAM, 16 QAM, and 8 QAM. The cable operator configures the partial service mode trigger value for the channel to be 16 QAM. When the channel becomes impaired and the modulation mode drops to 16 QAM, the present invention will transition the channel into partial service mode. This means the channel is marked as unusable for all bonded modems using it, such as the DOCSIS 3.0 cable modem 142. The bonded modems still have multiple channels to pass data on. Now all the bandwidth that the DOCSIS 3.0 cable modem 142 was using is now available for use by the DOCSIS 1.1 modem 182 and DOCSIS 2.0 modem 192. If the channel becomes more impaired and the modulation mode drops to 8 QAM, the present invention does not place the DOCSIS 1.1 modem 182 and DOCSIS 2.0 modem 192 in as much danger of being dropped with the reduction of bandwidth because the bonded modems are not using the channel. If the channel impairment decreases and the modulation mode only goes back to 16 QAM, the DOCSIS 3.0 cable modem 142 is still not able to use the channel but there is more bandwidth for the DOCSIS 1.1 modem 182 and DOCSIS 2.0 modem 192. If the channel impairment then goes away and the modulation mode for the channel goes back to 64 QAM, the channel comes out of partial service because the modulation mode is greater than the trigger mode and the bonded modems are able to reuse the channel again. Thus, there was no unnecessary load balancing or fear of losing modems in the move. In addition, voice calls on the DOCSIS 1.1 modem 182 and DOCSIS 2.0 modem 192 were probably not affected. The DOCSIS 3.0 cable modem 142 still had multiple channels to use and the DOCSIS 1.1 modem 182 and DOCSIS 2.0 modem 192 had their share of bandwidth.
The modulation modes do not have to hit exactly on the trigger value for the channel or configured modulation mode. If the channel goes from 64 QAM to 8 QAM with a trigger value of 16 QAM, then the channel goes into partial service because the active modulation mode went below the trigger value. The same holds true for coming out of partial service. If the channel goes from 8 QAM to 32 QAM it comes out of partial service because the active modulation mode is better than the trigger mode.
Although the disclosed embodiments describe a fully functioning method and computing device of transitioning into and out of partial service mode to make valuable bandwidth available for other resources, the reader should understand that other equivalent embodiments exist. Since numerous modifications and variations will occur to those reviewing this disclosure, the method and computing device of transitioning into and out of partial service mode to make valuable bandwidth available for other resources is not limited to the exact construction and operation illustrated and disclosed. Accordingly, this disclosure intends all suitable modifications and equivalents to fall within the scope of the claims.

## Claims

1. A method, comprising:
setting a trigger value for a channel, wherein a first cable modem and a second cable modem have registered to use the channel, and wherein the first cable modem is a bonded channel modem that utilizes a bonding group that includes the channel and at least one other channel;
monitoring a modulation mode for the channel;
transitioning the channel from full service mode to partial service mode when the channel is in full service mode and the monitoring detects that the modulation mode is less than or equal to the trigger value, wherein transitioning the channel from full service mode to partial service mode comprises marking the channel as unusable for cable modems that support channel bonding, whereby all bandwidth of the channel in partial service mode is made unavailable for use by the first cable modem and all bandwidth of the channel is made available for use by one or more cable modems that do not support channel bonding; and
transitioning the channel from partial service mode to full service mode when the channel is in partial service mode and the modulation mode for the channel is greater than the trigger value.

2. The method of claim 1, wherein the setting of the trigger value further comprises:
receiving the trigger value for the channel; and
storing the trigger value for the channel.

3. The method of claim 1, wherein the trigger value is at least one of a modulation mode for the channel, a modulation mode for a spectrum group, and a priority for a modulation profile hopping rule.

4. The method of claim 1, wherein the transitioning of the channel from full service mode to partial service mode further comprises:
notifying the first cable modem that the channel is in partial service mode, thereby marking the channel as unusable by the first cable modem.

5. The method of claim 1, wherein the transitioning of the channel from partial service mode to full service mode further comprises:
notifying the first cable modem that the channel is in full service mode, thereby marking the channel as usable by the first cable modem.

6. The method of claim 1, wherein the first cable modem is a DOCSIS 3.0 modem, and wherein the second cable modem is at least one of a DOCSIS 1.X modem, and a DOCSIS 2.X modem.

7. A computing device, comprising:
a memory device resident in the computing device; and
a processor disposed in communication with the memory device, the processor configured to:
set a trigger value for a channel, wherein a first cable modem and a second cable modem have registered to use the channel, and wherein the first cable modem is a bonded channel modem that utilizes a bonding group that includes the channel and at least one other channel;
monitor a modulation mode for the channel;
transition the channel from full service mode to partial service mode when the channel is in full service mode and the monitoring detects that the modulation mode is less than or equal to the trigger value, wherein transitioning the channel from full service mode to partial service mode comprises marking the channel as unusable for cable modems that support channel bonding, whereby all bandwidth of the channel in partial service mode is made unavailable for use by the first cable modem and all bandwidth of the channel is made available for use by one or more cable modems that do not support channel bonding; and
transition the channel from partial service mode to full service mode when the channel is in partial service mode and the modulation mode for the channel is greater than the trigger value.

8. The computing device of claim 7, wherein to set the trigger value, the processor is further configured to:
receive the trigger value for the channel; and
store the trigger value for the channel.

9. The computing device of claim 7, wherein the trigger value is at least one of a modulation mode for the channel, a modulation mode for a spectrum group, and a priority for a modulation profile hopping rule.

10. The computing device of claim 7, wherein to transition the channel from full service mode to partial service mode, the processor is further configured to:
notify the first cable modem that the channel is in partial service mode, thereby marking the channel as unusable by the first cable modem.

11. The computing device of claim 7, wherein to transition the channel from partial service mode to full service mode, the processor is further configured to:
notify the first cable modem that the channel is in full service mode, thereby marking the channel as usable by the first cable modem.

12. The computing device of claim 7, wherein the first cable modem is a DOCSIS 3.0 modem, and wherein the second cable modem is at least one of a DOCSIS 1.X modem, and a DOCSIS 2.X modem.

13. A system, comprising:
a cable modem termination system (CMTS) that stores a trigger value for a channel, and that monitors a modulation mode for the channel;
a first cable modem registered to use the channel, wherein the first cable modem is a bonded channel modem that utilizes a bonding group that includes the channel and at least one other channel;
a second cable modem registered to use the channel,
wherein when the channel is in full service mode and the modulation mode for the channel is less than or equal to the trigger value, the CMTS transitions the channel from full service mode to partial service mode, wherein transitioning the channel from full service mode to partial service mode comprises marking the channel as unusable for cable modems that support channel bonding, whereby all bandwidth of the channel in partial service mode is made unavailable for use by the first cable modem and all bandwidth of the channel is made available for use by one or more cable modems that do not support channel bonding; and
wherein when the channel is in partial service mode and the modulation mode for the channel is greater than the trigger value, the CMTS transitions the channel from partial service mode to full service mode.

14. The system of claim 13, wherein the trigger value is at least one of a modulation mode for the channel, a modulation mode for a spectrum group, and a priority for a modulation profile hopping rule.

15. The system of claim 13, wherein to transition the channel from full service mode to partial service mode, the CMTS notifies the first cable modem that the channel is in partial service mode, thereby marking the channel as unusable by the first cable modem.

16. The system of claim 13, wherein to transition the channel from partial service mode to full service mode, the CMTS notifies the first cable modem that the channel is in full service mode, thereby marking the channel as usable by the first cable modem.

17. The system of claim 13, wherein the first cable modem is a DOCSIS 3.0 modem, and wherein the second cable modem is at least one of a DOCSIS 1.X modem, and a DOCSIS 2.X modem.

18. A non-transitory computer-readable medium, comprising computer-executable instructions that, when executed on a computing device, perform steps of:
setting a trigger value for a channel, wherein a first cable modem and a second cable modem have registered to use the channel, and wherein the first cable modem is a bonded channel modem that utilizes a bonding group that includes the channel and at least one other channel;
monitoring a modulation mode for the channel;
transitioning the channel from full service mode to partial service mode when the channel is in full service mode and the monitoring detects that the modulation mode is less than or equal to the trigger value, wherein transitioning the channel from full service mode to partial service mode comprises marking the channel as unusable for cable modems that support channel bonding, whereby all bandwidth of the channel in partial service mode is made unavailable for use by the first cable modem and all bandwidth of the channel is made available for use by one or more cable modems that do not support channel bonding; and
transitioning the channel from partial service mode to full service mode when the channel is in partial service mode and the modulation mode for the channel is greater than the trigger value.